Pulpar temperature changes during mechanical reduction of equine cheek teeth: Comparison of different motorised dental instruments, duration of treatments and use of water cooling

Occurrence and Progression of Dental Abnormalities in the Black Fronted Duiker (Cephalophus niger) Due to Deficient Diet and Extreme Weather Phenomena

This study aims to assess the contributory and predisposing effects of prolonged drought and climate phenomena on the occurrence of dental abnormalities among three age groups of the black duiker (Cephalophus niger). 36 skulls comprised of 18 females and 18 males were examined. Each group consisted of 8 kids (age range 0-10 months) (4 males and 4 females), 14 mature individuals (age range 1-3 years) (7 males and 7 females) and 14 adults (age range older than 3½ years) (7 males and 7 females). It was observed that the most severe defects occurred in mature and old females during prolonged drought. Morphologic disruptions of the dentition occurred more frequently on the mandible relative to the maxilla. 93% showed apical dental aberration. Bone resorption occurred in 30% and 6% of females and males respectively with profile aberrations at both time stages, tooth staining was observed in 40% of females and 8% of males, attrition accounted for 15% in each of both sexes, 28% and 3% of the females and the males had missing teeth respectively with more occurrence in the premolars and the molar teeth. Calculus was found in 4% and 9% of the females and males respectively. These findings may be useful in determination of likely age and season for occurrence of dental pathologies, in evaluation of response to irrigation and may provide information to assist in bioremediation of dental pathology.

Equine Dental Floating (Crown Osontoplasty)

Odontoplasty (floating and occlusal equilibration) is the most commonly performed procedure in equine dentistry. From an anatomic perspective, an irregular occlusal surface, prominent cingula, transverse ridges, and enamel points all contribute to the function, form, and longevity of the equine cheek tooth. With limited reserve crown available and an average functional life range between 18 and 25 years, removal of tooth structure should be conservative. The authors consider a quality oral examination to be the most important dental procedure performed in the horse. Individual tooth evaluation should lead to a specific diagnosis and treatment plan. Tooth odontoplasty should be site-specific.

Thermotransduction and heat stress in dental structures during orthodontic debonding : Effectiveness of various cooling strategies

OBJECTIVES

Recent studies have indicated possible thermal damage to pulpal tissue during orthodontic debonding. This study aimed to analyze the thermal loads acting upon dental structures and their transfer to the pulp during orthodontic debonding. Specific goals were to analyze temperature changes in local dental tissues, thermotransduction to the pulp cavity, and the effectiveness of common cooling strategies and of simulated intrapulpal circulation.

MATERIALS AND METHODS

Metal brackets were bonded to five extracted human molars and subsequently removed. While a carbide bur was applied to debond the residual composite from the tooth surface, various cooling strategies (no/air/water cooling) were employed with or without simulated intrapulpal circulation, accompanied by temperature measurements with a thermographic infrared camera on the enamel surface and with measuring probes in the pulp cavity. Appropriate evaluation software was used to calculate the enamel-to-pulp temperature gradients and for statistical analysis.

RESULTS

Significant differences in temperature rise and heat development over time, both on the enamel surfaces and in the pulp cavities were found. The mean temperature rises associated with no/air/water cooling were 90.7/46.6/9.2 °C on the enamel surface versus 9/8/4.6 °C inside the pulp. However, thermotransduction from enamel to pulp remained below 10 % of the surface measurements in all groups. Simulated intrapulpal microcirculation was found to significantly reduce intrapulpal temperature levels.

CONCLUSION

During debonding of residual bracket adhesives, provided that a carbide bur is properly used, our data indicate a low risk of reaching critical intrapulpal temperatures even in the absence of dedicated cooling and no risk if the instrumentation is accompanied by air or water cooling.

Intra-pulp temperature increase of equine cheek teeth during treatment with motorized grinding systems: influence of grinding head position and rotational speed

BACKGROUND

In equine practice, teeth corrections by means of motorized grinding systems are standard procedure. The heat resulting from that treatment may cause irreparable damage to the dental pulp. It has been shown that a 5.5°C temperature rise may cause severe destruction in pulp cells. Hence, the capability to continuously form secondary dentine is lost, and may lead, due to equine-typical occlusal tooth abrasion, to an opening of the pulp cavity.To obtain reliable data on the intra-pulp increase in temperature during corrective treatments, equine cheek teeth (CT) were modified in a way (occlusal surface smoothed, apical parts detached, pulp horns standardized) that had been qualified in own former published studies. All parameters influencing the grinding process were standardized (force applied, initial temperatures, dimensions of pulp horns, positioning of grinding disk, rotational speed). During grinding experiments, imitating real dental treatments, the time span for an intra-pulp temperature increase of 5.5°C was determined.

RESULTS

The minimum time recorded for an intra-pulp temperature increase of 5.5°C was 38 s in mandibular CT (buccal grinding, 12,000 rpm) and 70 s in maxillary CT (flat occlusal grinding, 12,000 rpm). The data obtained showed that doubling the rotational speed of the disk results in halving the time span after which the critical intra-pulp temperature increase in maxillary CT is reached. For mandibular CT, the time span even drops by two thirds.

CONCLUSION

The use of standardized hypsodont CT enabled comparative studies of intra-pulp heating during the grinding of occlusal tooth surfaces using different tools and techniques. The anatomical structure of the natural vital hypsodont tooth must be kept in mind, so that the findings of this study do not create a deceptive sense of security with regard to the time-dependent heating of the native pulp.

A long-term study on the clinical effects of mechanical widening of cheek teeth diastemata for treatment of periodontitis in 202 horses (2008-2011)

REASON FOR PERFORMING STUDY

Cheek teeth diastemata are a common cause of painful periodontal disease in horses, but there is limited objective information on their treatment.

OBJECTIVE

To assess the long-term response to diastema widening in clinically affected horses.

STUDY DESIGN

Retrospective study.

METHOD

Medical records from cases of cheek teeth diastemata treated by diastema widening referred to the University of Edinburgh Equine Hospital from 2008 to 2011 were analysed.

RESULTS

During this period, 302 horses were diagnosed with clinically significant cheek teeth diastemata, of which 202, median age 11 years, with severe associated periodontitis were treated by widening of 674 problematic diastemata; 89.8% between mandibular cheek teeth and 10.2% between maxillary cheek teeth, with a mean of 1.5 treatments performed per case. These 202 cases showed quidding in 76.2%; weight loss in 33.2%; bitting problems in 20.1% and halitosis in 10.9%, with 5.4% being asymptomatic. Follow-up of 92% of treated cases, a mean of 20.8 months after their initial treatment, showed that 72.6% had complete remission of clinical signs that was permanent (for the duration of this study) in 50.5% and temporary in 22%. A partial response was obtained in 17.2%, no response was obtained in 4.3%, and owners were unsure of response in 5.9%. Clinical improvement was sometimes delayed, with 19% taking >4 weeks following treatment for improvement. Inappropriate sites were burred in individual teeth of 6 horses, causing iatrogenic pulpar exposure in 2 cases, but following treatment none developed clinical signs of apical infection.

CONCLUSIONS

Diastema widening is an effective but potentially invasive treatment for horses with cheek teeth diastemata with severe periodontitis.

POTENTIAL RELEVANCE

Diastema widening by trained personnel is suitable for advanced cases of cheek teeth diastema, but many cases require repeated treatments.